7/4pi multiplied by 180/pi give you about 97 degrees when you calculate it.
Answer:
19.3795 m
Step-by-step explanation:
If sound travels at 343 m/s and it took Karen 0.113 s to hear the echo from the wall, the distance travelled by the sound is:

Note that the distance calculated above is the distance travelled from Karen to the wall and then back from the wall to Karen. Therefore, the distance between Karen and the wall is:

The wall is 19.3795 m away from Karen.
Well, first you would have to draw the three pizzas, then spilt them all in half, so each friend would have a half of pizza! Hope this helped!